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Chapter 4—Striped Bass, Neotropical Migrants, Wild Turkey
This chapter highlights species that are points of focus during the summer months. The
following accounts and information on the black bear, loggerhead sea turtle, and
largemouth bass will explain why these species are important wildlife resources and what
is being done to responsibly manage these species. You can go directly to any of these
sections by clicking on their name: Striped Bass, Neotropical Migrants, Wild Turkey.
NEOTROPICAL MIGRATORY BIRDS
BACKGROUND INFORMATION:
Birds are among the most easily observed wildlife species in Georgia. Unlike
many of their mammalian counterparts, the vast majority of birds are diurnal, and are
often fairly tolerant of human presence and observation. Of the 407 bird species that
have occurred in Georgia, about 90 are neotropical migrants, which means they breed in
the United States and Canada but winter in Mexico, the Caribbean, or Central and South
America.
Tropic of Cancer
Tropic of Capricorn
Not only are many of these
birds brightly colored and
spectacular birds to observe, their
feats of prolonged endurance and
navigation during migration are
truly staggering. Imagine the
Ruby-throated Hummingbird
(Archilochus colubris), weighing
less than a penny, flying non-stop
over the Gulf of Mexico, a
continuous 24-hour flight of about
500 miles.
Wintering ground for our neotropical migrants.
WHO ARE OUR NEOTROPICAL MIGRANTS?
Most of our neotropical migrants are songbirds, a diverse group distinguished
from other birds by a unique split voice-box that produces their often beautiful and
complex songs. They range from the dazzlingly colored wood warblers and orioles, to the
earth-tone thrushes and flycatchers. Neotropical migrant songbirds include the
flycatchers (Tyrannidae), vireos (Vireonidae),
thrushes (Turdidae), swallows (Hirundinidae), wood
warblers (Parulidae), tanagers (Thraupidae), and
orioles (Icteridae). Other families of birds migrate as
Painted Bunting Image from Thayer Birding
Software
well, and neotropical migrants are found among waterfowl (Anatidae), shorebirds
(Charadriidae & Scolopacidae), vultures (Cathartidae), raptors (Accipitridae &
Falconidae), cuckoos (Cuculidae), swifts (Apodidae) and hummingbirds (Trochilidae).
Though many of these species spend most of the year in the Tropics, they are very
much a part of temperate ecosystems in the summer. Their ecological and economic
value is so great that it is difficult to calculate. Literally tons of insects are consumed by
neotropical migrants each summer and many plant species depend on these birds to
disperse their seeds and pollinate their flowers. Many of these birds are also sensitive
indicators of environmental health. An example of birds as bioindicators is the decline of
Peregrine Falcons, Bald Eagles, and Brown Pelicans due to DDT in the environment.
WHY MIGRATE?
Especially among the migratory songbirds, annual mortality associated with
migration is high, in some years probably exceeding 50%. Increased nesting success
achieved by migrating to the temperate zone must compensate for the high mortality
associated with migration, or the whole system
would collapse. This pattern does tend to
immerge as neotropical migrants are able to raise
more offspring (4-6 eggs per clutch) than similar
species that remain in the tropics (2-3 eggs per
clutch). A number of factors contribute to greater
temperate productivity. Species typically face
less competition, less predation, and a seasonally
abundant supply of food during the northern
summer. They are also able to spread out over 8
times the land area available to them in the
4 Ovenbird eggs on a nest in north Georgia
tropics.
This explanation of migration is a more positive one than an older notion of birds
flying south to avoid cold. As many species demonstrate, if a reliable food source is
available year-round, they will not migrate. Think of the tiny Golden-crowned Kinglet
(Regulus satrapa) that can survive nighttime temperatures of -30F in New England
where they spend the winter.
HOW DO BIRDS MIGRATE?
Blackpoll Warblers (Dendroica striata) weighing less
than an ounce leave the coast of New England on clear
autumn nights when winds are favorable and fly straight out
over the North Atlantic. Their trajectory would take them
straight to North Africa; however, the trade winds blow the
flying birds back westward, guiding them to landfall in the
tropical forests of Venezuela after a 3-4 day flight. This
astounding flight is carried out without stopping, sleeping,
eating, or drinking. This is the equivalent of a human athlete
running 4-minute miles for 80 hours straight. How are these
Trade
Winds
Southward
migration
of
Blackpoll
Warblers
tiny bundles of feathers, muscle and blood capable of such astounding feats of physical
endurance? Just as important, how do they know where they are going and find their
way?
THE CONSTRAINTS OF FLIGHT:
The ability to fly allows birds access to every corner
of the globe. This ability comes at a great price however, as
flight places major constraints on a bird’s anatomy and
physiology. The most obvious hurdle that migratory birds
must overcome is that of keeping a very low body weight,
while still being able to generate the power to keep
themselves aloft. This remarkable balance is achieved by a
Ruby-throated hummingbird
number of adaptations, including a simplified skeletal
Image from Thayer Birding
structure, hollow bones, and large keel that anchors powerful
Software
flight muscles to the rib cage. Some shorebirds, that fly nonstop over 6,000 miles of ocean, allow their internal organs including intestines, kidney
and liver to atrophy before the flight, further reducing their weight.
Despite all of these adaptations, migration still provides a unique challenge that
calls for extreme preparation. As the late summer days begin to shorten, hormonal
changes are triggered that cause birds to dramatically increase the amount of food they
eat. In a period of several weeks birds can nearly double their body weight in fat, the
critical fuel they will burn on long migratory flights.
NAVIGATION:
Today it is hard to imagine navigating without maps, compasses, and Global
Positioning Systems, yet birds have been accurately charting their migratory journeys for
millennia without such aids. A number of environmental cues, however, are available to
a migrating bird. The simplest form of navigation involves following known features
such as rivers, coastlines and mountain ranges. Some birds are able to use a variety of
more subtle cues including the stars, solar position, sense of smell, and even the earth’s
magnetic field to navigate. With this combination of tools, birds are able to navigate with
remarkable accuracy. Researchers studying of Red-eyed Vireos (Vireo olivaceus), a
common breeding bird in eastern deciduous forests, discovered that individual males
returned to the same West Virginia territories for five years in a row. Considering that
Red-eyed Vireos winter in the western Amazon Basin and northern South America, this
is truly remarkable.
HUMANS AND NEOTROPICAL MIGRANTS
Humans have certainly noticed and appreciated birds
for thousands of years. This appreciation most likely focused
primarily on the culinary and costume potential of birds.
Exploitative market hunting of birds for food and fashion
raised concerns about bird populations as early as the 1840’s.
This concern was warranted, as evidenced most tragically by
the extinction of the Passenger Pigeon (Ectopistes migratorius)
and Eskimo Curlew (Numenius borealis). Laws passed in the
early 1900’s provided legal protection for all of our native
Carolina Parakeets were killed
as agricultural pests
non-game species. Now it is illegal to possess feathers, nests or eggs of any of these
protected species. Several other southeastern bird species were also driven to extinction
through overhunting or habitat loss. These include the Carolina Parakeet (Conuropsis
carolinensis) and Bachman’s Warbler (Vermivora bachmanii).
Greatly aided by the availability of pocket field guides and affordable optics, the
non-consumptive enjoyment of birds has dramatically increased since the days of market
hunting. Bird watching is currently one of the most popular outdoor recreation activities
in the United States, with 46 million people spending $32 billion annually on bird related
sales. This in turn has generated over 860,000 jobs nation-wide.
CONSERVATION
Analyses of data from several nation-wide bird surveys have recently confirmed
anecdotal evidence of population declines for many bird species. The most important is
the Breeding Bird Survey that has collected data on birds since 1966 at about 2,000 sites
throughout the United States and Canada. Though it is impossible to generalize about all
species and regions of the country, most biologists agree that many species, especially in
the eastern United States seem to be facing significant population declines. Partners in
Flight has placed 100 bird species of conservation concern on a Watch List due to low or
declining population trends. See Table 1 for these species that occur in Georgia.
Table 1. Partners in Flight Watch List Species that occur in Georgia.
Highest Priority
Red-cockaded Woodpecker
Kirtland’s Warbler
Bachman’s Sparrow
Golden-winged Warbler
Henslow’s Sparrow
Saltmarsh Sharp-tailed sparrow
High Priority
Swallow-tailed Kite
Short-eared Owl
Red-headed Woodpecker
Olive-sided Flycatcher
Willow Flycatcher
Brown-headed Nuthatch
Wood Thrush
Prairie Warbler
Bay-breasted Warbler
Cerulean Warbler
Prothonotary Warbler
Worm-eating Warbler
Kentucky Warbler
Canada Warbler
Painted Bunting
Dickcissel
Rusty Blackbird
Priority
Blue-winged Warbler
Swainson’s Warbler
Nelson’s Sharp-tailed Sparrow
Seaside Sparrow
Though market hunting is a thing
of the past, birds still face a number of
threats. The loss and fragmentation of
habitat associated with urban sprawl and
development is probably the most serious
threat to most bird species today.
Fragmentation of habitat often allows
predators and nest parasites better access to nesting birds.
Beyond habitat loss or alteration, there is an increase in dispersed mortality
factors that accompany the growth of human populations and technology. These include
a wide variety of problems, from bird collisions with
Breeding Bird Survey population data for
communication towers and buildings, to predation by house
Cerulean Warblers
cats and mortality from pesticides.
House cats are often considered the largest predator on songbirds in the United
States. Several estimates suggest that cats kill hundreds of millions of birds a year in the
United States alone. This has led the American Bird Conservancy to start a Cats Indoors
program to encourage more responsible pet ownership.
An added complication for protecting neotropical migrants is that by definition,
they are highly mobile. To fully protect them, we must preserve not only their breeding
grounds, but migratory stopover sites and wintering habitat as well. Because these birds
winter in other countries, international cooperation is critical to their preservation. An
example of this challenge was a massive hawk die-off in 1996 in Argentina, where DDT
killed an estimated 20,000 Swainson’s Hawks (8% of the world’s population). DDT had
been illegal for over 20 years in the United States, but is still heavily used overseas.
WHAT IS BEING DONE?
The Georgia Department of Natural Resources is committed to the conservation
of all wildlife species, and is involved widely in the conservation of our neotropical
migratory birds. The Non-game Wildlife Section of Georgia’s Wildlife Resources
division is involved in education, research and monitoring of threatened species, ongoing
management of habitat, and acquisition of important habitat for wildlife. The Non-game
section helped establish birding festivals and trails to promote awareness of our
neotropical migratory birds. These education efforts include the Pinewoods Bird
Festival, and the Colonial Coast Birding Trail. Research projects are currently underway
to establish management strategies for some of our most threatened migratory birds, such
as Golden-winged, Cerulean and Swainson’s Warblers. We are also involved in a
number of surveys to monitor populations of our migratory birds. WRD works with
private landowners to help them manage land for our migratory birds. A good example is
the collaboration with large landowners to conserve breeding habitat for Swallow-tailed
Kites. Also, critical new habitat is purchased or protected in order to preserve or create
habitat for migrants. The Game Management section manages large amounts of land
called Wildlife Management Areas (WMA’s) for all wildlife, especially game species.
These WMA’s typically provide excellent habitat for our neotropical migratory species as
well.
CONCLUSION
With over 200 species of neotropical migrants nesting in the United States, there
is a huge amount to learn about their various habitats, behaviors, and population status.
As some of the most attractive and easily observed wildlife species, bird watching is
becoming increasingly popular among people of all ages. There are a number of citizen
science programs that amateur birders can become involved with that can add
significantly to our knowledge of migratory birds (see below).
How can you help?
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Learn more about and enjoy Georgia’s neotropical migrants
Improve backyard habitat for birds by providing
o Food – plant flowering and fruiting plants, nectar and seed feeders
o Water – dripping birds baths or small backyard ponds
o Shelter – wide variety of plant structure from the ground up, brush piles
Limit your use of chemical pesticides in your yard
Keep your cats inside
Join a local or national bird conservation organization
Support Georgia’s Non-game Wildlife Program with direct contributions, tax
check-offs, or by purchasing Wildlife Tags for your vehicle.
Learn to be a responsible consumer. Purchase products produced in the Tropics
that do not harm neotropical migratory birds. A good example is Shade Grown
Coffee.
Prairie Warbler by Deb Zaremba
FREQUENTLY ASKED QUESTIONS
If I leave hummingbird feeder up in the fall will it keep the birds from migrating?
No. Day length triggers migratory behavior, not the availability of food. In fact,
by leaving hummingbird feeders up year-round you have the chance that a rare western
hummingbird will visit your yard. Several species western hummingbirds winter in the
southeast in small numbers. If hummingbirds visit your feeder in winter, you should
report them to the Rare Bird Alert, because they will not be the Ruby-throated
Hummingbird, our one common breeding species.
What should I do if I see a baby bird on the ground?
Unless there is either an immediate threat (a stalking cat), or an obvious injury,
leave the bird where it is. Adult birds stay with their young even after they leave the nest.
Most birds’ first attempts at flight are not an unmitigated success, so most will spend
some time on the ground until they get the hang of it. The baby bird is much more likely
to die in captivity than in the wild.
What should I do if I find an injured bird?
There are many wildlife rehabilitators throughout the state of Georgia that are
able to care for injured birds. You can access this list by calling any Wildlife Resource
Division office or the Special Permit Unit at (770) 761-3044.
Where and when can I go to see migratory birds?
The best time to observe the largest number of species is during the spring and
fall migration. In Georgia, the last two weeks of April form the peak of the spring
migration, while September is the peak of the fall migration. In the summer breeding
neotropical migrants are found across the state, but the Blue Ridge Mountain region of
Georgia has the greatest diversity. Many state and national parks and wildlife
management areas provide excellent bird watching opportunities. For specific sites, see
Giff Beaton’s Birding Georgia listed below.
Can I keep bird feathers and nests if I find them in the wild?
No. Unless you have a salvage permit, you should leave all bird bones, feathers,
eggs and nests alone. The Migratory Bird Treaty Act of 1918 decreed that all migratory
birds and their parts (including eggs, feathers and nests) were fully protected. A salvage
permit must be acquired from the US Fish and Wildlife Service, and is typically available
to school teachers, nature centers and other educators.
What can I do to keep hawks from eating birds at my feeder?
By putting out birdseed, you attract seed eating birds. This very fact means that
you are likely to attract bird predators. Hawks are fully protected predators. If you can’t
accept the fact that a hawk might take one or two you really need to stop feeding the
small birds.
What is a good field guide to learn about birds?
There are a number of excellent field guides available today. Some use
photographs and others paintings. Generally, the paintings are considered better at
capturing the variability commonly found within a single species, though much is
dependant on your personal preference. Two of the top guides available today are the
National Geographic Field Guide to the Birds of North America, and the Sibley Field
Guide to Birds of Eastern North America.
What is shade-grown coffee, and does it really help birds?
Coffee originated as an understory plant, growing in the shade of canopy trees.
Recent forms however have been developed that can live in full sun. This has led to the
clearing of tropical forests and a 90% reduction of bird species in coffee plantations.
Shade-grown coffee plantations remain second only to undisturbed forest for quality bird
habitat. More information and locations for purchasing shade-grown coffee can be found
on at www.atlantaaudubon.org, and the Smithsonian Institute
http://nationalzoo.si.edu/ConservationAndScience/MigratoryBirds/Coffee/.
CITIZEN SCIENCE PROJECTS:
Generally require some basic bird identification ability, Internet access, and a place to
watch birds.
Project Feeder Watch, Great Backyard Bird Count (with National Audubon Society)
The Birdhouse Network, Project Pigeon Watch and others are organized by the
Cornell Lab of Ornithology. Visit http://birds.cornell.edu or www.birdsource.com for
more details.
Breeding Bird Survey: Require good bird identification skills by sight and sound.
Contact Non-game Wildlife office to get more information. (478) 994-1438 or visit the
Patuxent Wildlife Center (USGS) site http://www.pwrc.usgs.gov/
Christmas Bird Count: Longest running citizen science project in the US.
Dates can be found at www.gos.org (web site for Georgia Ornithological Society)
BIRD CURRICULUM:
Project Flying WILD
Bird curriculum designed to help middle school students put on a bird festival. Includes
many hands-on activities and events. Visit www.flyingwild.org or www.projectwild.org
Audubon Adventures – 4-6th grade curriculum. A classroom kit includes materials for
32 students: Student Newspaper, lesson plans, tips for outdoor study, hands on activities
and guide to a healthy schoolyard. Visit www.atlantaaudubon.org education link.
Friends of Feathered Fliers, Interactive Educational Activity Box: Borrow for FREE!
Includes: Videos, binoculars, bird eggs, nests, lesson plans, books, and posters. Sign out
from local nature centers around state. www.partnersinflight.org
Project WILD Activities www.projectwild.org
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Changing the Land
Rare Bird Eggs for Sale
Shrinking Habitat
Migration Barriers (deer not birds)
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No Water Off a Ducks Back
Hazardous Links, Possible Solutions
Birds of Prey
Bird Song Survey
Create Bird Habitat at home or school:
Several organizations help schools develop wildlife habitat in schoolyards for education
and conservation.
Atlanta Audubon Society - www.atlantaaudubon.org
Georgia Wildlife Federation (GWF) – www.gwf.org
Both offer guidelines to create water, food, shelter and space for wildlife. For
funding ideas see http://birds.cornell.edu/schoolyard
Bird Conservation Organizations:
American Bird Conservancy
Provides information on a wide range of conservation topics, such as the Cats Indoors
Campaign. Cats kill hundreds of millions of birds each year in the US alone, as well as
other wildlife species. – www.abcbirds.org
Local Chapters of the Audubon Society
Lead bird walks open to public of all ages. Often have monthly meetings with interesting
speakers. Several have regular newsletters. Atlanta Audubon Society teaches a Master
Birder Class for those interested in delving more deeply into the study of birds.
Atlanta Audubon Society
www.atlantaaudubon.org
All Georgia’s Bird clubs and local Audubon chapters can be found at
http://www.gos.org/local-ga-orgs.html
National Audubon Society
http://www.audubon.org
Partners in Flight
International cooperative group of federal, state, and private organizations working to protect
migratory landbirds. www.partnersinflight.org
OTHER RESOURCES:
Birding Georgia – A Falcon Guide, Giff Beaton, 2000 – More than 100 places in Georgia to look
for birds.
Annotated Checklist of Georgia Birds – Available from the Georgia Ornithological Society
Handbook of Bird Biology – Cornell Lab of Ornithology, 2004. Excellent Ornithology Text.
Birding Software – Pictures and calls for all North American Species. Natural History
information on all species. Games to help learn birds.
http://www.ebird.org
http://www.hummingbirds.net - site with lots of good hummer info – migration maps –
tracking northward and southward movement –
Supplemental Material (PDF files)
Bluebird Box Plans – simple plans to construct a nesting box for Eastern Bluebirds.
Nuthatch Box Plans – simple plans to construct a nesting box for nuthatches.
Screech Owl Box Plans – simple plans to construct a nesting box for Eastern Screech Owls.
Why Birds are crazy for coffee Fact Sheet – Information on “bird-friendly coffee”.
Neotropical Migrant basic Fact Sheet – Basic information about Neotropical Migrants.
Have Wings will Travel Fact Sheet – Basic information on migration.
Cat Predation Fact Sheet – Basic information on the problem of cat predation.